Excitation of waves in the pulsar magnetosphere. Color bar shows the components of the electromagnetic field multiplied by ﹩{(r/{r}_{\star })}^{2}﹩. Top : E _∣∣ in the quasi-steady state. The dashed white curve shows the null surface ρ _GJ = 0 (the null surface breathes outside r _LC due to plasmoid motion). Insets (i)-(iii): electromagnetic modes excited during e ^± discharges at the polar cap, inner return current, and outer return-current gaps. Inset (iv): waves excited by a beam plasma instability. For insets (i) and (ii), δ E _⊥ is calculated by projecting δ E _⊥ onto a unit vector in the ﹩\hat{{\boldsymbol{\phi }}}\times {\boldsymbol{B}}﹩direction.